Fluids based on fluorocarbon compounds are widely used in vapor-compression heat-transfer systems, especially air-conditioning, heat pump, refrigeration or freezing devices. The common feature of these devices is that they are based on a thermodynamic cycle comprising vaporization of fluid at low pressure (in which the fluid absorbs heat); the compression of the vaporized fluid up to a high pressure; the condensation of the vaporized fluid to liquid at high pressure (in which the fluid expels heat); and the depressurization of the fluid to complete the cycle.
The choice of a heat-transfer fluid (which may be a pure compound or a mixture of compounds) is dictated firstly by the thermodynamic properties of the fluid, and secondly by additional constraints. Thus, a particularly important criterion is that of the impact of the fluid under consideration on the environment. In particular, chlorinated compounds (chlorofluorocarbons and hydrochlorofluorocarbons) have the drawback of damaging the ozone layer. Non-chlorinated compounds such as hydrofluorocarbons, fluoro ethers and fluoroolefins are thus now generally preferred.
It is, however, necessary to develop other heat-transfer fluids that have a lower global warming potential (GWP) than that of the heat-transfer fluids currently used, and which have equivalent or improved performance qualities.
Document US 2009/0 143 604 describes processes for manufacturing fluoro alkanols and fluoroolefins. The synthesis of 2,3,3,4,4,4-hexafluorobut-1-ene (HFO-1336yf) is especially disclosed.
Document WO 2009/085 937 describes a secondary cooling loop system for an air conditioning system. Among the heat-transfer compounds that may be used is HFO-1336yf.
Document US 2009/0 302 264 describes heat-transfer compositions comprising a heat-transfer fluid, a lubricant and an acidic deactivator. HFO-1336yf is cited among the possible heat-transfer fluids.
Document US 2011/0 088 418 describes compositions comprising an ionic liquid and a fluoroolefin, which are useful for heat-transfer applications with absorption systems. HFO-1336yf is cited as an example of a fluoroolefin.
However, there is still a need to develop other heat-transfer fluids that have a relatively low GWP, and that are capable of replacing the usual heat-transfer fluids.
In particular, it is desirable to develop other low-GWP heat-transfer fluids that are quasi-azeotropic and/or that have good energy performance qualities when compared with the usual heat-transfer fluids (such as isobutane) and/or energy performance qualities that are better than those of the known low-GWP heat-transfer fluids.